I've had this now for over 3 years and is my go to for my shorter runs that required hydration or for races that have aid stations every 4-8 miles. I've used this training, 50K, 50M, 100K, and 100M races where aid stations are fairly close that I can refill the single water bottle. The shoulder pockets are great for nutrition, headlamp, zip lock bags of sports drink mix, and spare batteries. The back storage is great for today's larger phones. My old Google Pixel 2 use to fit great on the shoulder pockets but my Pixel 7 barely fits so I put it in the back. Both of my 100 mile trail runs, this was excellent to reduce weight but still provide hydration and some quick storage. Any training runs over 18 miles or my 100 mile bike rides, my Endurance Pack V2 has been my workhorse.
Downside, I have to use it with a shirt with sleeves. I tried running in a tri-singlet and it caused me some chafing. Never had any issue with a shirt on.